8.2 Introduction to Mining and Mineral Processing

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The 13th Annual Americas School of Mines Introduction to Mining and Mineral Processing* *connectedthinking W. Scott Dunbar Department of Mining Engineering University of British Columbia Part B: Mining Methods

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Transcript of 8.2 Introduction to Mining and Mineral Processing

  • The 13th AnnualAmericas School of Mines

    Introduction to Mining and Mineral Processing*

    *connectedthinking

    W. Scott DunbarDepartment of Mining EngineeringUniversity of British Columbia

    Part B: Mining Methods

  • PricewaterhouseCoopers

    Introduction to Mining and Mineral Processing

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    Slide 2

    Part B: Mining Methods

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    Mining Methods: The Topics

    Open Pit Mining

    Mining Processes &Mining Equipment

    Underground Mining

    Click on any of the topic icons below to view the slides on that topic

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    Open Pit Mining

    Generally low grade, shallow ore bodies

    Mining rate >20,000 tpd

    Non-selective all high and low grade zones mined

    Design issues: stripping of overburden

    location of haul roads

    equipment size of trucks and fleet

    pit slope angle and stability

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    Bagdad Pit Arizona looking west

    Porphyry copper 170,000 tpd 9,200 ft 5,800 ft pit828 Mt sulfide and oxide reserves:0.28% Cu, 0.022% Mo (2007 10K filing)

    Copper concentrate, Molybdenum concentrateSX/EW leach plant for low grade sulfides Pressure leach facility for roasting molybdenite

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    Notes: Bagdad Pit Arizona looking west

    First claims staked in 1882. Property changed ownership numerous times through first half of 20th century. First millbegan operation in 1928 to process ore from the underground mine. Transition to open-pit mining began in 1945. A$240 million expansion in 1973 included new haul trucks, shovels, nearly 400 housing units and concentrator. Bagdadbecame part of the Phelps Dodge mining portfolio in 1999 with the acquisition of Cyprus Amax Minerals Co. In 2007,Freeport McMoran merged with Phelps Dodge.

    The ore is a porphyry with disseminated primary sulfides (chalcopyrite and molybdenite). Low grade secondarysulfide and oxide ores are present which are soluble by acid.

    Copper and molybdenum concentrates with gold and silver credits are produced and smelted at the Miami smelter.Copper is produced at a SX/EW plant for oxide ore (operating since 1970) and at a new (2003) concentrate leachfacility, the worlds first.

    Source: http://www.fcx.com/operations/USA_Arizona_Bagdad.htm

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    Highland Valley Pit British Columbia

    Porphyry copper, 170,000 tons mined/day (tpd)451 Mt reserves: 0.38% Cu, 0.007% Mo (2007 Teck Cominco report)

    90% of production from Valley pit Copper concentrate with gold and silver, Molybdenum concentrate

    N

    Valley Pit

    H-H tailings dam

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    Notes: Highland Valley Pit British Columbia

    The Highland Valley Copper mine, located in British Columbia, 60 km southwest of Kamloops is 97.5% owned by TeckCominco.

    Operations at Highland Valley began over 22 years ago by predecessor companies. The present operation is acombination of the Lornex mine and mill, the Valley Copper orebody and the Highmont mine and mill. The presentmill is the old Lornex mill into which Highmont mill equipment was integrated.

    The Valley pit contains two in-pit crushers feeding a 12,000-tonne per hour conveying system that delivers ore tostockpiles at the mill. Ore from the Lornex mine is hauled to two permanent crushers with discharge to commonstockpiles.

    Concentrates are transported by rail eastward to domestic markets and to Vancouver for shipment to overseasmarkets.

    The life of the mine has been extended from 2013 to 2019. The new mine plan will require a push-back of the westwall of the Valley pit. Total capital costs of the expansion project are estimated at $300 million, including $130 millionfor capital equipment and the balance in pre-production stripping over the period of 2009 through 2013.Approximately $50 million of mobile mining equipment will be ordered in 2007 to permit waste stripping tocommence in 2009.

    Source: Teck Cominco 2006 Annual Report

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    Cortez Gold Mine Nevada

    Three deposits in area: Pipeline, Cortez Hills, Pediment86.5 Moz reserves, ore grade: 0.08 oz/t

    Gold production 2007: 323,000 oz

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    Coal and Oil Sands Mines

    Eagle Mountain, BCFording Coal

    Suncor mine Fort McMurray, Alberta

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    Notes: Coal and Oil Sands Mines

    Coal and tar sands operations typically involve moving large amounts of waste (often called overburden) to gainaccess to the economic mineral.

    Eagle Mountain is part of the Fording River operations in southeastern British Columbia. Fording River producesboth metallurgical (coking) coal for the steel industry and thermal coal for power plants in Alberta. Fording River'smeasured and indicated reserves total over 200Mt of clean coal plus a further 286Mt in resources, over 65% ofwhich is contained in the Eagle Mountain deposit. The coal has a low sulfur content and its volatile content rangesfrom medium to high. Three distinct coking coal types are available at Fording River. Fording River can mine at a rateof 10Mt/year or about 28,000 tpd.

    Source: http://www.mining-technology.com/projects/fording

    Oil sand is a mixture of bitumen (a thick sticky form of crude oil), sand, water and clay. The Suncor Mines extract oilsand from mines north of Fort McMurray in Northern Alberta. Using shovels with 100 ton buckets and 240 and 360ton trucks the mine extracts about 450,000 tonnes of oil sands per day. The material is crushed and sized and madeinto a slurry which is delivered to the processing plant via 86 km (54 mi) of pipelines In the plant, the sands aremixed with hot water to separate the oil from the sand. In 2005 the Suncor Mines produced 171,300 barrels ofbitumen per day, which, after upgrading, is ready for refining. Suncors leases contain a resource of more than 13billion barrels of bitumen.

    Source: www.suncor.com

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    Pit slopes and their stability

    Rock is stronger than sand so

    angle of repose

    can be larger.

    45 usually the maximum

    Pit slopes are benched

    ~30

    At the beachIn an open pit

    35-45

    pushbacks

    ore

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    Notes: Pit slopes and their stability

    An open pit mine is developed as a series of nested pits, each larger in area than the previous pit. A pushback is the removal of material required to proceed from one pit to the next. The revenue from the ore must pay for the cost of excavating the waste from the pushback and for excavating the ore. But the slope cannot exceed 45 and remain stable so at some point it becomes impossible and/or uneconomic to continue mining.

    Pit slopes are cut into benches to aid stability and contain any slope failures.

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    Straight faults and circular holes

    North Pit, Homestake Pitch Mine, Sargents Colorado

    Pit rim

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    Notes: Straight faults and circular holes

    As the magma containing the minerals for an orebody rises up, it generates stresses in the host rock,rupturing it and causing faults. Thus most orebodies are related to faulting in the earths crust. Faultsare long linear features and so if an orebody is mined with a circular pit, it is likely to intersect a fault.This can lead to instability in at least two parts of the pit slope.

    Source:

    Cremeens, J., 2003. Geologic controls on complex slope displacement at the Pitch reclamation project.Engineering Geology in Colorado, Contributions, Trends, and Case Histories. AEG Journal

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    Pit Wall Stability at Bagdad

    North wall (2008)

    West wall (2007)

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    Notes: Pit Wall Stability at Bagdad

    The north wall is undergoing a pushback in order to gain access to ore near the bottom ofthe pit. It is expected that about 2-3 years of excavation will be required to achieve a stableslope. There are some stability problems on the north wall due, in part, to a near verticalfault which runs through the wall.

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    Dewatering pump at Cortez Nevada

    water table is drawn down to

    keep pit dry

    pump

    There are 40 of these around the Cortez pit pumping water out of the ground at a total rate of 30,000 gallons perminute in order to keep the pit dry. Dewatering also helps to keep the slopes dry and more stable.

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    Strip Ratio

    Applies to an open pit mine

    SR is the mass of waste to be mined to obtain one unit mass of ore. Examples:

    Oil sands deposits in Alberta: SR = 1.0-1.5Highland Valley: SR ~0.45 (2007 Teck annual report)Bagdad mine: SR =1.4 (2007 FCX 10K filing, p.5, but oxide ore also mined see notes)Cortez mine: SR = 2.2 (2007 Barrick annual report)

    WasteStrip ratio = Ore

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    Notes: Strip Ratio

    Mistakes are often made when computing the strip ratio. Its all in the words and you have to watch the flow ofmaterial and how it is classified. For example, according to Freeport McMorans 2007 10K filing, the concentrator iscapable of processing 75,000 metric tons per day of primary sulfide ore and the mining fleet is capable of moving180,000 metric tons per day. Thus If everything is working to capacity (and it usually works close to capacity) and thematerial moved is assumed to be waste plus primary sulfide ore, the strip ratio is (180-75)/75 = 1.4.

    However, the material moved includes waste plus oxide/secondary sulfide ore and primary sulfide ore. The 10K filingand other information provided does not classify the amounts mined. However, the 2005 Phelps Dodge report statesthat Bagdad mined 64,093 thousand tons (kt) of material and processed 26,592 kt in the concentrator. The reportalso states that 23,857 kt of ore (oxides/secondary sulfides) was placed on the leach stockpiles. This means thewaste is 64093-26,592-23,857 = 13,644 kt, about 21% of the material mined. So does this mean their strip ratio,waste/ore = 0.21/0.79 ~ 0.27

    Not so fast. According to footnote h on page 11 of the 2005 report the leach ore includes previously consideredwaste material that is now being leached. This means that some leach ore was mined prior to 2005 and was re-classified from waste to ore. The report does not state how much was mined in 2005 and placed on the leachstockpile but, according to a contact at Bagdad, the amount mined was minimal the 23,857 kt is mostly a re-classification.

    Hard to define a strip ratio when what was waste becomes ore and vice versa.

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    Example: Large open pit

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    Underground Mining

    Generally high grade deposits

    More selective than open pit

    Design issues: geometry of underground

    mining

    ground support

    shaft location

    logistics of underground materials transport

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    Underground Mine Anatomy

    Future reserves?

    Producing stopes

    ShaftMined out

    stopes

    Stopes under development

    Levels

    Source: Atlas Copco

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    Notes: Underground Mine Anatomy

    In general for underground mines:Small output mines (4,000 tpd) - a main haulage level is used and all the ore is dropped to that haulage level via ore passes.

    A level includes all the horizontal workings tributary to a shaft station. Ore excavated in a level is transported to the shaft to be hoisted to the surface.Stopes are openings from which ore is mined. They may be backfilled with cemented waste material. Ore passes are sub-vertical chutes for movement of ore. Declines or ramps are spiral or inclined drifts.Note the different types of drilling: development drilling to open up the orebody and exploration drilling to better define the limits of the orebody.

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    Going underground ..Sinking a vertical shaft

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    Cut and Fill Mining

    Stopes

    Fill is some combination of

    tailings and cement

    Source: Atlas Copco

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    Notes: Cut and Fill Mining

    Cut-and-fill mining removes ore in horizontal slices, starting from a bottom undercut and advancing upward.Ore is drilled, blasted and removed from the stope. When a stope is mined out, the void is backfilled withsand tailings and cement or waste rock. The fill serves both to support the stope walls and provide a workingplatform for equipment when the next slice is mined.There are two types of cut and fill mining overhand and underhand. In overhand cut and fill, the ore liesunderneath the working area and the roof is backfill. In underhand cut and fill, it is the opposite, the oreoverlies the working area and the machines work on backfill.Cut-and-fill mining is applied to steeply dipping orebodies in stable rock masses. It is a selective miningmethod and is preferred for orebodies with irregular shape and scattered mineralization. Because themethod involves moving fill material as well as a significant amount of drilling and blasting, it is relativelyexpensive and therefore is done only in high grade mineralization where there is a need to be selective andavoid mining of waste or low grade ore.

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    Narrow Vein Mining

    Hanging wall(above vein)

    Footwall(below vein)

    Source: Atlas Copco

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    Notes: Narrow Vein Mining

    Used for very narrow orebodies, as small as a half metre wide. Very selective method; waste rock isleft in hanging wall and footwall. In a wide vein, a standard LHD can operate inside the drift. Slim-size machines including drill rigs, jumbos, and 2 m3 bucket LHDs, are available for working in drifts asnarrow as 2.0 m.

    Note: It is called the hanging wall because that is where miners used to hang their lamps whileworking. It is called the footwall because that is where their feet were planted. Nowadays, theillumination is provided by an electric grid within the mine and all miners wear headlamps on theirhardhats.

    On the right is a photo of a very narrow vein, longhole stope at Gympie Eldorado Mine, Gympie,Queensland, Australia.The drive is 2.5m wide and the stope is 0.9m wide.

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    StopingLonghole stopingSublevel stoping

    Stope

    Blasted ore (muck)

    Drilling and

    blasting

    Source: Atlas Copco

    Stope

    Blasted ore (muck)

    Drilling and

    blasting

    Source: Atlas Copco

    Requires less drilling than

    sublevel stoping

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    Notes: Stoping

    Stoping is used for mining deposits with following characteristics:

    Steep dip, the footwall inclination must exceed the angle of repose

    Stable rock in both hanging wall and footwall

    Both competent ore and host rock

    Regular ore boundaries

    Sublevel stoping recovers the ore from open stopes separated by access drifts each connected to a ramp. Theorebody is divided into sections about 100 m high and further divided laterally into alternating stopes and pillars. Amain haulage drive is created in the footwall at the bottom, with cut-outs for draw-points connected to the stopesabove. The bottom is V-shaped to funnel the blasted material into the draw-points.

    Short blastholes are drilled from the access drifts in a ring configuration. The ore in the stope is blasted, collected inthe draw-points, and hauled away. The stopes are normally backfilled with consolidated mill tailings after beingmined out. This allows for recovery of the pillars of unmined ore between the stopes, enabling a very high recoveryof the orebody.

    Longhole stoping uses longer (~100 m) and larger diameter blastholes, thus requiring less drilling than sublevelstoping. Greater drilling accuracy is required and non-planar irregularities in the orebody shape cannot berecovered. .

    Development of the infrastructure for both these stoping methods is time-consuming, costly, and complex.

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    Potash Mining just grind away

    Photo source www.saskmining.ca/photoLib.php?SEC=Potash

    Potash (used to make fertilizer) is so soft, it can be crushed and ground in place, eliminating the needfor blasting. The potash ore is transported by conveyor to the shaft and hoisted to the surface.

    conveyor

    Four rotor boring machine

    Three passes in potash seam to make 20 m wide room

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    Room and Pillar Oil Shale Mine in NE Estonia

    Source: www.aapg.org/explorer/divisions/2006/05emd.cfm

    ~2.5 m

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    Wieliczka salt mine

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    Longwall Mining of Coal

    Coal Entry tunnels

    Passagew

    ay

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    Notes: Longwall Mining of Coal

    Longwall mining is a highly mechanized underground mining system for mining coal. A layer of coal is selected andblocked out into an area known as a panel. A typical panel might be 3000 m long by 250 m wide. Passageways wouldbe excavated along the length of the panel to provide access and to place a conveying system to transport materialout of the mine. Entry tunnels would be constructed from the passageways along the width of the panel.

    The longwall system would mine between entry tunnels. Extraction is an almost continuous operation involving theuse of self-advancing hydraulic roof supports sometimes called shields, a shearing machine, and a conveyor whichruns parallel to the face being mined. A typical configuration of a longwall mining system is illustrated below on theleft.

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    Sublevel caving below a mined out pit

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    Notes: Sublevel caving below a mined out pit

    Sublevel caving is usually carried out underneath an open pit when it becomes uneconomic to minefrom the pit. The underground orebody is typically a relatively narrow slab that dips at a steep angle.The method is similar to sublevel stoping except that the ore breaks into fragments (caves) by itselfafter an initiating blast, i.e., the blast does not do all the fragmentation.

    Underground mining proceeds by constructing tunnels (drifts) through the orebody at different levelsbelow the bottom of the pit. Holes are drilled up into the roof of each tunnel (longhole drilling), loadedwith explosives, and blasted to cave the roof. After the roof caves in, Load Haul Dump (LHD) vehiclestransport the muck to an ore pass where it is lifted to the surface. Drilling and blasting is sequenced insuch a way that mining can take place at different levels of the mine at the same time.

    As the muck is transported to the ore pass, more blasting is done to cause ore to cave into the drifts.This is repeated until the entire orebody is depleted. Ultimately rock from the pit will cave into theunderground.

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    Block Caving an upside down open pit

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    Notes: Block Caving an upside down open pit

    Applicable to large, deep, low grade deposits. There are several block cave mines in Chile. Block cavingat a depth of two km is being considered for the Resolution deposit east of Phoenix.

    A grid of tunnels is driven under the orebody. This can take a significant amount of time, but therewards are high in terms of production rate. The rock mass is then undercut by blasting. Ideally therock breaks under its own weight. The broken ore is then taken from draw points. There may behundreds of draw points in a large block cave operation. Essentially block caving creates anunderground inverted open pit. Production rates are high. Surface subsidence can be a problem.

    Mine Tons/dayEl Teniente CopperSouth of Santiago, Chile

    EsmeraldaSub 64 South

    45,00035,00035,000

    Andina Copper and Molybdenum100 km north of Santiago, Chile

    35,000

    Northparkes Copper and GoldAustralia

    14,000

    Henderson MolybdenumWest of Denver, Colorado

    36,000

    Palabora Copper South Africa

    35,000

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    Fragmentation at Northparkes

    Source: SRK International Newsletter No. 28

    Good

    Bad

    Large fragments may cause hang-ups stopping the flow of ore. They have to be broken up by secondary blastingwhich can be costly because a set of draw points near the blasting has to be shut down..

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    Block Cave Operations

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    Why all these underground methods?

    High operating

    cost

    Low operating

    cost

    Cut and fill Stoping CavingLongwallRoom and pillar

    Backfill support

    No backfillControlled

    collapse

    High flexibility

    Low flexibility

    Low operating cost, bulk mining operations such as block caving are desirable, but the capital costs for developmentof mines that use these methods are significant. In addition, there is little flexibility in a bulk mining operation itmust produce ore at a high rate almost without fail.

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    A complex ore body

    West Zone

    East Zone

    Source: Terry Gong and Daniel Avar, 2006. Resource Estimation and Mine Design. Feasibility Report written for MINE 491 course at University of British Columbia.

    WARNING: Never lose sight of your guide if you go underground. The various twists and turns in anunderground operation make it very easy to get lost.

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    Same ore body different mining methods

    West Zone

    East Zone

    Source: Terry Gong and Daniel Avar, 2006. Resource Estimation and Mine Design. Feasibility Report written for MINE 491 course at University of British Columbia.

    WARNING: Never lose sight of your guide if you gounderground. The various twists and turns in anunderground operation make it very easy to get lost.

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    The Mining Cycle

    Blast

    Ventilate (underground)

    Load with explosives

    Drill holes

    Load, haul, dump

    Install support (underground)

    Survey blastholes

    Scaling (underground)

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    Underground drilling

    Drill jumbo

    Remotely operated rig drilling into a stope

    A jumbo drill is several drills (up to five) mounted on one machine and powered by a single drive system. Thesemachines show conclusively that it is possible to do more than one thing at a time while underground.

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    Drilling in an open pit

    Tricone bit

    Air is forced down the drill stem and out through holes in thedrill bit. The tricone bit may be cooled with water.

    Air Rotary Drill at

    HVC

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    Blasting

    Blast at Zaldivar mine, Chile

    www.mining.ubc.ca/cimarchive/bymine.htm

    Its never good to see a blasting technician smiling whenstanding next to a rock face loaded with explosives.

    Blast pattern at Highland Valley

    The idea is to break rock, not air!

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    Notes: Blasting

    The picture on the left of the slide shows some cones in drilled holes ready for explosives to be pouredinto them. Note the regular pattern of the blast holes. There is also a pattern to the detonation timesof the explosives in each blast hole. Typically the detonation times of the explosives in two adjacentblast holes differ by a few milliseconds (called a delay time) so that the blast proceeds in a particulardirection within the blast pattern. Very cool to see the detonation pattern.

    Blasts should not vent and be too spectacular. If they are, it is a mistake, wasted energy. The goal isto keep the blast energy in the ground to fracture the rock as much as possible.

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    Load Haul and Dump

    A dirty scooptram

    Terex O&K RH400 shovel (100 ton, $12M)

    10 tonne scooptram

    ~$100K

    Terex MT6300AC truck (400 ton, electric, $5-6M)

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    Notes: Load Haul and Dump

    The Terex RH400 shovel (50 m3 capacity) is used to load Caterpillar 797B trucks (380 ton capacity) at Syncrude Minein Alberta. The Terex O&K RH400 shovel was designed specifically to meet Syncrudes high capacity and durabilityneeds in the oil sands.

    Image sources: www.terex.com www.agnico-eagle.com

    Cocktail party trivia:

    Every 24 hours at Syncrude there is enough metal worn off the mining equipment, by abrasive oil sand, to make twofull-size pick-up trucks. Source: www.syncrude.com

    The fuel tank of the Caterpillar 797 truck has a capacity of 6,800 litres (1800 gallons) thats 12,364 extra large cupsof coffee or 19,155 cans of pop.

    The Cat 797s tires are nearly 4 m (13.1 ft) tall, weigh 15,422 kilograms (34,000 lb), and cost $50,000 each (US$).

    The goal of large machines is to spread fixed costs over a larger unit, i.e., obtain economies of scale. However, there isconcern that maintenance costs of these large machines, particularly tire costs, are too high leading to diseconomiesof scale. One manufacturer has suggested 1000 ton haul trucks by 2020. Shovels will become correspondingly larger say 150 m3. But

    It may not be possible to build tires for such large trucks

    New materials and new designs may be needed to build the trucks

    Space constraints on haul roads and maintenance facilities

    Total production and transportation costs increase with size

    There are reliability and flexibility issues if one large machine breaks down, the system stops

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    Install supportMesh and rockbolts

    Shotcrete

    Swellexbolt

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    Notes: Install support

    Rock is strong when it is compressed it takes a huge force to break rock by squeezing it. In the earth, rock issubjected to very large compressive forces due to the weight of rock lying above it. However, opening a hole in rocktakes away this compressive force and the rock expands, maybe only a few millimeters, but this expansion is enoughto cause failures along cracks. The expansion actually pulls the rock apart and rock is weak when this happens it issaid to be weak in tension.

    Thus cracks form on the roof and walls of a mine opening and the rock mass begins to fall apart. This might lead tolarge (dangerous) chunks of rock forming on the roof and walls. When these fall into the opening, it is called spalling.The mesh prevents this.

    A compressive force can be imposed on the rock mass around a mine opening by means of rock bolts. These are longsteel bars with wedges on one end that lock them into place at the end of a hole drilled from the mine opening. A nuton the other end of the bolt is tightened to provide compression to the rock mass by squeezing it together.

    Shotcrete is a thin layer of concrete that is sprayed onto the rock face. It can take the place of mesh and is easier toinstall, but it can be expensive. Sometimes short narrow plastic rods are embedded to provide tensile strength to theshotcrete (Concrete is also weak in tension thats why rebar is used in concrete construction.) Shotcrete can alsoprovide some strength by preventing further expansion of the rock mass into the opening.

    What is used depends on the rock type and its conditions. It also depends on the use of the opening e.g.,permanent or temporary.

    Slide 54

    Part B: Mining Methods

  • PricewaterhouseCoopers

    Introduction to Mining and Mineral Processing

    Lack of selectivity of mining method

    Grade control and dilution

    Equal length blast holes drilled into waste

    Ore

    Bench in Pit

    Waste

    Slide 55

    Part B: Mining Methods

  • PricewaterhouseCoopers

    Introduction to Mining and Mineral Processing

    Notes: Causes of Dilution

    It is often difficult to mine selectively and avoid dilution. In open pit operations, efforts are being made to use global positioning satellite systems (GPS) and other methods to accurately position drills and individual shovel scoops. In underground operations, some work is being done to separate waste from ore at the source, i.e., before it goes up the shaft.The amount of dilution varies depending on the orebody type and geometry and on quality control in mine operations. A typical assumption for dilution in open pit mines is 10% (meaning that 10% of ore extracted is actually waste) while the assumption for dilution in underground mines is typically 15%. However, these must be considered estimates in the absence of information.

    Slide 56

    Part B: Mining Methods

  • PricewaterhouseCoopers

    Introduction to Mining and Mineral Processing

    These things happen

    WARNING: Keep clear of haul trucks if you findyourself in an open pit mine. The drivers field ofview is very limited.

    A really stupid mistake

    The story below is that the driver happened to be eating his lunch on the passenger side of the pickup when the haul truck drove over it. He survived.

    Slide 57

    Part B: Mining Methods

  • *connectedthinking

    END OF PART B

    Part B: Mining MethodsWhat do the symbols in the pdf file mean?Mining Methods: The TopicsOpen Pit MiningBagdad Pit Arizona looking westNotes: Bagdad Pit Arizona looking westHighland Valley Pit British ColumbiaNotes: Highland Valley Pit British ColumbiaCortez Gold Mine NevadaCoal and Oil Sands MinesNotes: Coal and Oil Sands MinesPit slopes and their stabilityNotes: Pit slopes and their stabilityStraight faults and circular holesNotes: Straight faults and circular holesPit Wall Stability at BagdadNotes: Pit Wall Stability at BagdadDewatering pump at Cortez NevadaStrip RatioNotes: Strip RatioExample: Large open pitUnderground MiningUnderground Mine AnatomyNotes: Underground Mine AnatomySlide Number 25Cut and Fill MiningNotes: Cut and Fill MiningNarrow Vein MiningNotes: Narrow Vein MiningStopingNotes: StopingPotash Mining just grind awayRoom and Pillar Oil Shale Mine in NE EstoniaWieliczka salt mineLongwall Mining of CoalNotes: Longwall Mining of CoalSublevel caving below a mined out pitNotes: Sublevel caving below a mined out pitBlock Caving an upside down open pitNotes: Block Caving an upside down open pitFragmentation at NorthparkesBlock Cave OperationsWhy all these underground methods?A complex ore bodySame ore body different mining methodsThe Mining CycleUnderground drillingDrilling in an open pitBlastingNotes: BlastingLoad Haul and DumpNotes: Load Haul and DumpInstall supportNotes: Install supportGrade control and dilutionNotes: Causes of DilutionThese things happenSlide Number 58